1. Field of the Invention
The invention relates to a chair, more particularly to a chair with an adjustable backrest.
2. Description of the Related Art
FIG. 1 shows a conventional highchair 1 disclosed in GB 2,358,793. The highchair 1 includes a seat 3 and a support structure 2. The seat 3 includes a body 13 with a sitting portion 15 and a backrest 14. The body 13 is provided with lateral sidepieces 16 (only one is visible) that are connected to lateral elements 7 (only one is visible) of the support structure 2. A control component 25 is disposed on a rear side of the backrest 14, and is operable in a direction (X) as shown in the Figure when it is desired to change an inclination of the seat 3.
The lateral elements 7 of the support structure 2 are provided with box structures 17 to connect the seat 3 to the support structure 2. Each box structure 17 has two portions (17I, 17II), and the corresponding sidepiece 16 of the seat 3 is positioned between the two portions (17I, 17II). An inverted U-shaped component 21 is disposed on the rear side of the backrest 14, and is driven by the control component 25. The inverted U-shaped component 21 includes a pair of lateral rods 23, each of which is provided with a coupling seat 28 and extends into the corresponding box structure 17. The coupling seat 28 is provided with a pin 29, which engages selectively one of three spaced apart grooves 35 formed in the corresponding box structure 17 upon operation of the control component 25 such that the seat 3 can be retained at a desired inclination relative to the support structure 2. A spring 37 connects a corresponding coupling seat 28 to the corresponding box structure 17 in order to provide a restoring force.
In use, the control component 25 on the rear side of the backrest 14 is operated to drive the two lateral rods 23 of the inverted U-shaped component 21 such that the pins 29 are disengaged from a current pair of the grooves 35 in order to permit adjustment of the backrest 14 to the desired reclining angle. After adjusting the backrest 14 to the desired reclining angle, the control component 25 is released, and the springs 37 (only one is visible) urge the lateral rods 23 and the associated pins 29 to engage another pair of the grooves 35 for retaining the seat 3 at the desired inclination.